(Phys.org) —In a typical man-made sonar system, pulses of sound emitted by the projector bounce off hidden objects underwater. The echoes are then detected by the receiver to infer the location and size ...

The evolution of similar traits in different species, a process known as convergent evolution, is widespread not only at the physical level, but also at the genetic level, according to new research led by ...

(PhysOrg.com) -- It has long been thought that dolphins produce sounds by means of "whistles," but a new analysis of a data gathered in the late 1970s has revealed that instead, dolphins make sounds by means ...

(PhysOrg.com) -- Scientists have long seen evidence of social behavior among many species of animals, both on the earth and in the sea. Dolphins frolic together, lions live in packs, and hornets construct ...

From barks to gobbles, the sounds that most animals use to communicate are innate, not learned. However, a few species, including humans, can imitate new sounds and use them in appropriate social contexts. ...

Dolphins are indeed sensitive to magnetic stimuli, as they behave differently when swimming near magnetized objects. So says Dorothee Kremers and her colleagues at Ethos unit of the Université de Rennes ...

The unusual river dolphins, some of them known for their poor eyesight and side-swimming behavior are all descendants of ocean-dwelling species. Until now, however, there has been no consensus about their ...

(PhysOrg.com) -- Scientists studying dolphin behavior have suggested they could be the most intelligent creatures on Earth after humans, saying the size of their brains in relation to body size is larger than ...

Alcohol consumption isn't the only thing a breath analysis can reveal. Scientists have been studying its possible use for diagnosing a wide range of conditions in humans—and now in the beloved bottlenose dolphin. In a report ...

A species of humpback dolphin previously unknown to science is swimming in the waters off northern Australia, according to a team of researchers working for the Wildlife Conservation Society, the American ...

A new study of dolphins and seals shows that despite their remarkable adaptations to aquatic life, exercising while holding their breath remains a physiological challenge for marine mammals. The study, published ...

Dolphin

Dolphins are marine mammals that are closely related to whales and porpoises. There are almost forty species of dolphin in seventeen genera. They vary in size from 1.2 m (4 ft) and 40 kg (90 lb) (Maui's Dolphin), up to 9.5 m (30 ft) and 10 tonnes (9.8 LT; 11 ST) (the Orca or Killer Whale). They are found worldwide, mostly in the shallower seas of the continental shelves, and are carnivores, mostly eating fish and squid. The family Delphinidae is the largest in the Cetacea, and relatively recent: dolphins evolved about ten million years ago, during the Miocene. Dolphins are considered to be amongst the most intelligent of animals and their often friendly appearance and seemingly playful attitude have made them popular in human culture.